Pneumatic-despatching-tube system.



No. 800,275. .PATENTBD SEPT. 26, 1905'.

I W. H. DINSPEL & J. J. STOETZEL.

PNEUMATIC DESPATCHING TUBE SYSTEM. a

APPLICATION FILED JUNE 17 1904 7 SHEETS-SHEET 1.

& E II 'NO- 800,275. PATENTED .SEPT. 26, 1905.

' W. H. DINSPEL & J. J. STOETZEL.

PNEUMATIC DESPATCHING TUBE SYSTEM.

APPLIOATIONVIILEDI JUNE 17, 1904.

7 SHEETS-SHEET, 3.

No. 800,275. PATENTED SEPT. 20, 1905.

W. H. DINSPBL & J. J. STOETZEL. PNEUMATIC DESPATGHING TUBE SYSTEM.

APPLICATION FILED JUNE 17, 1904.

7 SHEETS-SHEET 4.

Np. 800,275. PAlTENTED SEPT. 20. 1905.

W. H. DINSPEL & J. J. STOBTZEL.

PNEUMATIC DESPATGHING TUBE SYSTEM.

APPLIOATION FILED JUNE 17, 1904.

Y 7 SHEETS-SHEET 5 N n\\\ \\\E S Ir DREW I nu l4 c0 mom-mm! Kits. '1 SHMIT PATENTED- SEPT. 26, 1905. W. H. DINSPEL, & .T. J.. STOETZEL.BNEUMATIG DBSPATGHING TUBE SYSTEM:

APPLIUATIONI FILED mm; 11, 1904.

7 suns-sum e.

PATBNTED SEPT. 26,, 1905. z W.- H."DINSPEL & J. I. STOBTZEL. PNEUMATICDESPATGHING TUBE SYSTEM.

7 SHEETS-SHEET 7.

I UNITED 'sT TEs' PATENT, onion. 7 v

WILLIAM H. DINSPEL ANnJosErr'i J. STOETZEL, or ornoAeo, ILLINOIS.PNEUMATICeDESPATCH INC-I TUBE SYSTEM.

"Spec ification of Letters Patent.

Patented Sept. 26, 1905.

Application filed June 17, 1904. Serial No. 212,931.

To all whom it may concern.-

Be it known that we, WILLIAM H. DINSPEL and J OSEPH J. SToETznL,vcitlzens of the United States of America, and residentsof phicago, inthe countyzof Cook and State of Illinois, have invented certain new anduseful Improvements in Pneumatic-Despatching- Tube Systems, of which thefollowing is a specification; M

The main objects of this invention are to provide animproved form ofpneumatic-dc spatch-tube system which is economical. in structure andoperation and suitable for either long or short distance transmission;to provide improved means for supplying power in.

a long-distance pneumatic transmission system at a plurality ofrelay-stations along the line, thereby greatly reducing the frictionalresistance of the air passing through the system and making it possibleto operate such systems with less powerful machinery and smaller runningexpenses, to provide 1mdespatching mechanism, the supporting-frame Zproved means for automatically operating valves at the despatch end ofthe tube and at the various relays, so as to'allow carrier-car tridgesto be sent through the system in close sucoessionand at the same timeprevent the possibility of a plurality-of such cartridges becomingbunched at one point of the system and requiring great expenditure ofpower to move same, and to provide in a system of this class improvedautomatic mechanicallyoperated means for setting the relay-valvesthrough the action of the passing cartridge;

and without resorting to electrical connections which require attentionto prevent ineflioiency through corrosion-of connections, &c. Weaccomplish these objects by the device shown in the accompanyingdrawings, in which- Figure 1 is a diagrammatic View of a pneumatictransmission system constructed ac- Fig. 2 is a longifor some of theparts being omitted for the sake 'of-clearness, Fig. 3 isa longitudinalsection of one of the suction-valves on the line 3 3 of Fig, 4. Fig. 4.isa transverse section of the same on the line 4 4 of Figs, 3 and 5.Fig. 5 is a top plan, partly broken away,

of the suction valve operating mechanism, the full lines showing theposition of the parts corresponding with the open position of the valve.Fig. 6isalongitudinal section, partly broken away, of the relaymechanism. Fig.

tions.

the suction-pipe and adapted to maintain a vacuum in advance of acartridge passing along the tube, air-valves for admitting air behindthe cartridge at suitable intervalsalong the line, mechanism forautomatically operating the suction and air valves so as to carry acartridgethrough the system, together with a governing device actuatedby the vacuum in the system and controlling the operation of the pumpingmechanism.

- In the construction shown the suction-pipe 1 extends throughout theentire system and has ateach side of same and parallel therewith atransmission-tube 2, said tubes being adapted to carry cartridges inopposite direc- Air is exhausted from the suctionpipe 1 by means ofa-prirnary pump 3 and an auxiliary pump 4, both of said pumps beingdriven byxthe motor 5. The transmissiontubes are provided with valveswhich are normally closed to prevent air from entering such tubes, andthe tubes are connected with the suction-pipe by air-passages at theirterminals and at a plurality of relay-stations, one of which is shown oneach pipe in Fig. 1. The pump 4 is adapted to maintain a vacuum of acertain number of inches when the transmission-tubes are not in service,said pump being regulated to neutralize the leakage of air into thesystem. The pump 3 is of suificient capacity to maintain the desiredintensity of vacuum. It will be seen that the pump 3 need therefore beoperated only when the transmission-tubes are in service, and a gov-.ernor 6, actuated by the vacuum in the system, is provided forcontrolling the operation of said primary pump. The-pump L is drivendirectly from a belt 7, connected with the engine 5, while the primarypump 3 is driven by the belt 8 from the engine 5, with thegovserningmechanism 6 intervening. The belt8 drives a loose pulley 9, journal'edon theshaft 10, which connects with the pump The friction-clutch of thegoverning mech-- 'anism consists of an annular flange 1 1,'which v isrigid on the loose pulley 9,'and hub 12,

keyed to the shaft 10 within the flange 11 and adapted to havefrictional contact with the flange 11 through an annular shoe 13, whichis seated in an annular groove in the periphery of the hub 12 and isnormally out of engagement with the flange 11. A spirally-coiled pipe 11 separates the shoe 13 from the hub 12 and is adapted to expand underpressure and force the shoe 13 into frictional contact with the flange11, thus causing the shaft 10 to be driven through rotation of thepulley 9. end of the flexible pipe 1 1 is closed, while the other endconnects with a fitting 15, disposed axially of the shaft 10 andrevoluble'therewith and having swiveled water-tight connection at 16with a pipe 17. The pipe 17 communicates With the interior of acylindrical tube 18, within which are slidably mounted the piston-valves19 and 20, which are rigidly connected with each other and suitablyarranged so that their movement along the tube 18 will connect the pipe17 either with the inlet-pipe 21 or with an exhaust-pipe 22. The pipe 21communicates with a suitable reservoir, (not shown,) from which water issupplied under sufficient pressure to expand the tube 14 of the clutch.When the pistons are in the position shown in Fig. 8, the pipe 14: isconnected with the pipe 21 and water is admitted to the pipe 14, whichexpands and causes the pump 3 to be operated. i/Vhen the pistons movetoward the left, the piston 19 cuts off the connection between the pipes17 and 21 and permits of communication between the pipes 17 and 22,permitting the escape of the fluid from the tube 14: and causing same tocontract and permit the shoe 13 to move out of frictional engagementwith the flange 11, thereby stopping the pump 3.

Movement of the pistons 19 and is controlled by means of a diaphragm 23,which is connected to said valves by the rod 2 1. The diaphragm 23 isinclosed within a chamber 25. The right-hand side of the diaphragm isexposed to atmospheric pressure through the perforations 26 in the wallsof the chamber 25, while the otherside of the diaphragm communicatingthrough a suitable fitting 27, with the pipe 28, which connects with thesuction-pipe 1. The rod 24 extends through the diaphragm 23 and isseated in a bearing member 29, which is threaded into the fitting 27 andadjustable longitudinally of the rod 24:. A spiral spring 30 surroundsthe rod 24: and bears between the diaphragm 23 and the inner end of themember 29, normally urging the parts into the positions shown by thefull lines in the drawings. When the pressure within the suction-pipefalls, the air-pressure on the diaphragm 23 causes same to move towardthe left, thereby opening communication between the pipes 17 and 22,permitting the escape of liquid from the tube 14:, and consequentlystopping the pump 3. The tension One of the spring 30 is regulated tosuit any desired vacuum-pressure by adjusting the member 29. To preventslight fluctuations of the vacuum in the suction-pipe from atl'ectingthe clutch and to hold the parts at their limit of other movements, aweighted lever 31 is pivoted to the tube 18, connected with the rod 24.The weight on the lever is adjustable and tends to resist the movementof the valves until the lever passes its vertical position, when saidweight will assist in throwing the valves to the other limit of theirmovement.

The despatehing mechanism comprises a. receptacle 32, having a hingedcover 33, communicating with the receiving end of the tube 2 through avalved despatch-box 31-, together with suitable pneumatic mechanism foroperating the valves of the despatch-box. 'lhe receptacle 32 and itscover 33 are adapted to entirely inclose a cartridge for carryingarticles through the tube and are provided with apertures 35, having acombined area small compared to the area of the despatchtube 2. Thedespatch-box is provided with two valves extending across the path ofthe cartridge, the valve 36 being a sliding gatevalve, while the valve37 is a swinging valve pivoted at 38, opening inwardly of thedespatch-tube and normally braced in its closed position by means of atoggle-link strut 31). The despateh-box is further provided with anair-valve 4:0, pivoted at 11, opening to the outer air and locatedinward of the tube from the gate 36. The gate 36 is operated by a stem12, which is moved bymeans of a piston in the cylinder 43. The oppositeends of the cylinder 43 are connected, by means ol the pipes 1 1 and4:5, with an air-inlet 16 and are controlled by a three-way valve -17,operated by the handle 418 to admit air to either end of the cylinder,as desired. The ends of the cylinder are also connected in similarmanner to a pipe &9, connected with the suctionpipe and controlled bythe three-way valve 50. The valves 17 and are each provided with an arm51, connected by a link 52, as shown, so that when one end of thecylinder 43 is connected with the vacuum-pipe the other end will beexposed to atmospheric pressure. Asecond link 53 connects the link 52with a bell-crank lever A second cylinder 55 is located near thecylinder 13 and has a piston-rod 56, arranged to open the valves 40 and37. The member 57, at the lower end of the rod 56, is connected with thevalve 40 by means of a link 58, which has a slot at 59 at its upper endto permit a considerable upward movement of the stem 56 before the valve40 is opened. The togglestrut 39 is shown in its limiting position ascontrolled by the lug 60 on the link 61. The

arm 62 is rigid on the shaft 63, which connects, by means of a secondarm 61 and link 65 outside of the tube, with a trip-arm 66, having aweighted pawl 67 pivoted at its end.

The pawl 67 engages the member 57 in such manner that an upward movementof the pi'ston-rod 56 will raise'th'e arm 66 until the rotation of sucharm permits the pawl to slip off the end of the member 57. When themember 57 moves downward, the pawl 67 swings away to permit the member57 to pass below same. The upward movement of the main suction-pipe 1.The two ends of the cylinder 55 are further connected by means of aby-pass 72, controlled by a valve 73, through which the pressures on theopposite sides of the piston within the cylinder 55Ttend to equalizeeach other when the valve'69 is in its closed position, as shown in thedrawings.

The valve 73 -controls the equalization of pressures, and thereby timesthe descent of the piston in the cylinder 55. The by-pass .72 isconsiderably smaller than the air-inlet 68,

and therefore does not affect the movement of the piston when theair-inlet 68 isopened. The movement of the valve 69 is controlled by thecylinder 13 through engagement of part of the relay-fitting, and itsweight is counterbalanced by means of a spiral'spring 77, so that thegate is held normally open and is very sensitive and requires littleforce to close it. The tube communicates with the outer air at eachrelay-station through a valve 78, located beyond the gate 75 in thedirection of the movement of a cartridge passing along the tube, and asuction-valve 79 conmeets the transmission-tubewith the suctionpipe infront of the valve 75. The suctionvalve 79 is located a considerabledistance from the gate 75 in order that if the gate happens to be closedthe rare air in front of the cartridge during its passage between thesuction-valve 79 and the gate 75 will be compressed sufliciently tocausethe gate 75 to commence to open before being struck by the cartridge.-The face of the gate 75 is curved, as shown, so that a cartridgestriking same would tend to wedge the gate open rather than striking adirect blow upon same. The suction-valve 79 is normally open, butisclosed through the engagement of a passlng.

so that the difference in pressures between not affect the,sensitiveness'of the valve.

Within the valve-casing 81 are two cylindrical valve-seats 82, whichcommunicate,-

. through, the apertures 83, with annular passages'8 1, connected withthe suction-pipe -1.

'The valve-plates 85 are cylindrical and pro- 'vided with aperturescorresponding with the apertures 83 of, the valve-seats. The ends of thecylindrical valve-plates 85 are open and communicate with a passage 86,connected with the interior of the tube 2. The valveplates thuscohtrolthe connection between the tube 2 and the suction-pipe 1 and are openedand closed by being rocked on their shaft 87. An arm 88 is rigid on theshaft 87 and extends into sliding engagement with a cam-slot 89in thecross-head 90, which is slidably mounted in suitable guides in thevalve-casing. It will be seen from the drawings that a movement of thecross-head 90 along the valve-casing will cause the arm 88 to rotate thevalve-plate 85. Movement of the cross-head 90 is effected by means of arod 91, to which is connected a lever 92, fulcrumed at 93 on the tube 2.The cross-head 90 is normally urged in directidn for moving thevalve-plates 85 into their closed position through the action of thespring 94, which is normally under tension and has its ends secured,respectively, to the link 96 and a'fixed bracket 95. The'link 96, whichispivoted to the lever 9,2, passes' through a guide-aperture the arm ordetent 97, which is rigidly connected with the trip-lever 80, and thushold the valve in its open position. The arm 97 is adapted to be movedout of engagement with the link 96 through the contact of the cartridgewith the trip-lever 80, permitting the spring 945 to close the valve.The trip 80 is seated in ahousing 98, so that it may move entirely outof the path of the cartridge.

The valve 78 is opened by means of a rod 99, connected with the piston100 in the cylinder 101. The cylinder 101 is provided with an air-inlet124,, a suction connection 122, and a byl-pass 123, arranged in asimilar manner as the corresponding parts of the cylinder 55. Theair-inlet 124 is controlled by a valve 102 on a bell-crank lever 103,which eonnectswith a second bell-crank lever 104 by means of a link 105.The bell-crank lever 10 1 is loosely connected,,by means of a rod 106,with a trip 107,.which is mounted in a housing 108 above the tube 2 andextends ,into said tube, so as to be engaged by a passing cartridge.

When the trip 107 is lifted by the cartridge, it causes the .valve 102to open, and-thereby causes an upward movement of the piston 100'andopens the airvalve 78. As the piston-rod 99ffa'scends the lug 109engages the bell cranklever 102 and again closes the inlet 124,whereupon the'air in the cylinder 101 below the piston 100 graduallyescapes through the by-pass 123. This permits the Weight of the pistonto cause the same to gradually descend and close the valve 78. The rod99, through engagement with the bell-crank lever 110, which isrepresented by dotted lines in Fig. 6 and which is connected with therod 91, is thus also adapted to set the valve 79 in its open positionwhen the piston 100 ascends. This connection is also showndiagrammatically in Fig. 1.

' The terminal of the despatch-tube 2 is fitted with a flap-valve 111,opening outwardly and pivoted at 112 in a suitable hood 113, and isconnected by a pipe lit with the suctionpipe 1. The area of the pipe 114is considerably less than that of the despatch-tube 2 in order thatwhile the pipe 114: will normally maintain avacuum in the last sectionof the despatch-tube 2 a cartridge rapidly approaching the valve 111will compress the air in advance of same more rapidly than air is beingexhausted by the pipe 114 and will thereby cause the valve 111 to startto rise before beingengaged by the cartridge. The valve 111 ispreferably partly balanced by a spring 115, so as to offset the inertiaof the parts of such valve, as was the case of the relay-valve 75. Thetube 2 discharges upon a table 116, which is shown broken away in Fig.7. At the opposite side of the table 116 and opposed to the tube 2 is adash-pot 117, adapted to stop the advance of. the cartridge anddischarge same upon the table 116, which may be slightly inclined towardone side, so as to cause the cartridge to roll into a suitablereceptacle. (Not shown.) The dash-pot 117 comprises a cylindrical casing118, flared at the end opposed to the tube 2 and closed at its other endexcept for the usual air-escape aperture or apertures 119. A piston 120is slidably mounted within the casing and is normally urged toward theopen end of same by means-of a spring 121. It is preferred to providemeans for regulating the area of the air-escape apertures 119, as shown.

The operation of the system shown is as follows: As hereinbeforeexplained, it will be understood that the pump 4 is arranged to maintainthe vacuum within the system against the ordinary leakage of air throughthe valves and joints of same when the system is not in use, while thepump 3, through the action of the governor 6, operates only when theadmission of air to the system for the purpose of driving cartridgesthrough same requires such extra pumping power for the purpose ofmaintaining the vacuum at the desired intensity. To send a cartridgethrough the system, the cover 33 of the receptacle 32 is thrown open, acartridge is placed in such receptacle, and the cover closed. The lever48 is then turned downward, as shown by the arrow in Fig. 2, admittingair to the cylinder 4C3 below the piston therein, connecting the upperend of the cylinder with the suctionpipe by means of the three-wayvalves, as hereinbefore described, and causing the gate 36 to open. Asthe gate 36 opens the lug 74 on the rod 42 engages the lever 70, andthus causes the admission of air to the air-inlet 68 of the cylinder 55.This causes the member 57 to rise, causing the collapse of the joint ofthe toggle-strut 39 and permitting the opening of the gate 37. Thecartridge is now forced into the despatching-tube 2 by the pressure ofair behind same. Such movement is at first gradual on account of thelimited amount of air admitted by the contracted apertures 35. Continuedupward movement of the member 57 lifts the air-valve 10 and admitslarger quantities of air behind the cartridge, while the arm 57 becomesreleased from the member 57 and permits the closing of the valve 37,followed by the closing of the valve 36 through the reversal of thethree-way valves 17 and 50, which is caused by the lifting of thebell-crank lever 51 by the member 57. The valve 69 is simultaneouslyraised by the member 57 to close the air-inlet 68 in the cylinder 55.Leakage of air through the by-pass valve 73 now causes an equalizationof pressures in opposite ends of the cylinder 55 and allows the member57 to descend under the action of gravity and gradually close the valve10. The member 57 also passes below the pawl 67 on the lever 66 and intoposition for lifting such lever previous to the passage of anothercartridge. Through adjustment of the by-pass valve 73 the closing of thevalve 40 is regulated so that the valve will remain open sufficientlylong to cause the cartridge to be carried beyond the first relay-gate.As the cartridge passes the suction-valve 79 in its approach to arelay-station it engages the lever 80, tripping said lever andpermitting the valve to close. The air-pressure behind thecartridge,together with the momentum of such cartridge, causes same tocontinue along the tube and if the valve 75 is closed compressing theair in advance of same and finally lifting the gate 75 at therelay-station. The cartridge continues its movement under the suction inthe succeeding section of the tube and lifts the lever 107, opening thevalve 102 and causing the piston 100 to open the air-valve 78. The airrushing in through the valve 78 insures the closing of the gate 75 andsupplies new impelling force to the advancing cartridge. The rise of thepiston 100 also operates the bell-crank lever 110 and reopens thesuction-valve 79. The lever 80 falls back into position for engaginganother cartridge and locks the suction-valve in its open position. Itwill be understood that after the closing of the gate 75 and the openingof the suction-valve 7 9 the vacuum in the first seetion of the pipe isalmost instantly established and the tube is inreadiness forthetransmis-. 'sion of other cartridges, the gate 75 remain ing closeduntil after the valve 78 is closed and the pressures on both sections ofthe tube cartridge through the gate 111 said gate closes behind thecartridge and the vacuum is again established in the last section of thetube by the pipe 114. The compressionof air in advance of the cartridgenecessary for cartridge is overcome in the dash-pot 117,-

opening the valve 111 againstatmospheric pressure has the effect ofgradually reducing thespeed of the cartridge previous to its delivery.Any remaining momentum of the after which the cartridge is deliveredupon the table 116.

It will be seen that the relay mechanism herein shown is suitable forsupplying-the power from aplurality of pumping-stations located atintervals along the line, thus avoidnnit a cartridge along same; a gateextending ing the enormous losses in friction which occur when air mustbe pumped through long lengths of piping.

Itwill be seen that numerous details of the construction shown may bealtered without departing from the spirit of our invention.

What we claim as our invention, and desire to secure by LettersPatent,is

1. In a pneumatic-despatch-tube system, the combination of a tube; agate extending across said pipe and separating same into two sec tions;means for exhausting the air from each section of said tube; meansforclosing the gate after the passage of a cartridge; and a valve openingto the outer air and controlled by the passage of the cartridge. foradmitting air behind said cartridge after same has passed the gate,substantially as described.

2. In a pneumatic-despatch1tube system, the combination of a tube; agate extending across said tube and separating same into two sections;.means for exhausting the air from each section of said tube; means forclosing the gate after the passage of a cartridge; a valve opening tothe outer air and controlled by the passage of the cartridge foradmitting air behind said cartridge after same has passed the gate, anda timing device for controlling the closing of said valve, substantiallyas described.

3. In a pneumatic-despatch system,- the combination of a despatch-tubeadapted to transacross said tube; a spring adapted to balance the Weightof said gate; means for exhausting the air from said tube; asuction-valve communicating with said means and located in front of saidgate; mechanism operated by the cartridge and adapted to close saidvalve during the passage of the cartridge; said valve being locatedsufliciently far in front of said ,gate so that the air in the tubebetween said fvalve and gate will be compressed by the caritridge andstart the opening of said gate, substantially asdescribcd.

have becomeequalized. When the cartridge finally arrives at theterminal, it'again causes a compression ofair in advance of sameandopens the gate 111. After the passage of the 4. In apneumatic-despatch-tube system,the

transmit acartridge along same; a gate extending diagonally acrosssaidpipe, and being 5 suitably balanced so as to be normally open;:means. for admitting air to the tube behind j said gate and closingsame after the passage of acartridge; means for exhausting the air fromsaid tube; a suction-valve communicating with said means and located in.front'of said gate; mechanism operated by the cartridge and adapted toclose said valve during the passage of the cartridge, said valve beinglocated sufiiciently far in front of the gate so that the air in thetube between said valve and gate will be compressed by the cartridge andstart the opening of said .gate, substantially as described. I

5. In a pneumatic-despatch-tube system,the combination of a tubeadaptedto transmit a cartridge along same; a gate extending across saidtube .and dividing said tube into two sections; means for exhausting theair from each of said sections; a suction-valve in said first sectioncommunicating with said means; an air-lnlet valve communicating with thesecond section of said tube near said gate; and pneumatic means foropening said suction and air valves after the cartridge has passed saidgate;

substantially as described.

- 6. In a pneumatic-despatch-tube system,the combination of a tubeadapted to transmit a cartridge along same; a gate extending across saidtube and dividing same mto two sections;

means'for exhausting the air from each of said sections; a suction-valvein the first section communicating with said means; an airinlet valvecommunicating with the second section of said tube near said gate; andmeans controlled by the passage of said. cartridge and adapted to opensaid suction and air valves after the cartridge has passed said gate,substantially as described.

7. Ina pneumatic-despatch-tu be system, the

combination of a tube adaptedto transmit a cartridge along same; a gateextending across said tube and .dlvidlng same into two sections; meansfor exhaustlng the air from each of said sections; a suction-valve inthe first sectioncommunicating with said means; an airinletvalvecommunicating with the second section of said tube nearsaid gate;pneumatic means'for opening said suction and air .valves a trip in saidtube adapted to engage the car tridge after same haspassed said gate andoperate said pneumatic means substantially as described. v Y

after the cartridge has passed said gate; and

8. The combination of a cylinderpapistonlslidably mounted insaidcylinder;- means'for exhausting the air from one end of said cylinder;an air-inlet at the other end of said cylinder; a by-pass connecting theends of said cylinder, said by-pass being of less area than said inletand being adapted to equalize the pressures on the opposite ends of thepiston after said air-inlet has closed. substantially as described.

9. In a pneumatic-despatch-tube system,the combination of a tube adaptedto transmit a cartridge along same; means for exhausting air from saidtube; a valve for admitting air to said tube; a cylinder having a pistonslidably mounted therein and connected with the air-valve in the tube;means for exhausting air from one end of said cylinder; an air-inlet atthe other end of said cylinder; a by-pass connecting the ends of saidcylinder, said bypass being of less area than said inlet and beingadapted to equalize the pressure on the opposite ends of the pistonafter said air-inlet has closed, said piston being adapted to move whensaid air-inletis opened and thereby open said air-valve; a valvecontrolling said airinlet; and a trip in said tube adapted throughengagement With the cartridge to open said air-inlet valve,substantially as described.

10. In a pneumatic-despatch-tube system, the combination of a'tubeadapted to transmit a cartridge along same; means for exhausting airfrom said tube; a valve for admitting air to said tube; a cylinderhaving a piston slidably mounted therein and connected With theair-valve in the tube; means for exhausting air from one end of saidcylinder; an air-inlet at the other end of said cylinder; a by-passconnecting the ends of said cylinder, said by-pass being of less area.than said inlet and being adapted to equalize the pressure on theopposite ends of the piston after said air-inlet has closed, said pistonbeing adapted to move when said air-inlet is opened and thereby opensaid air-valve; a valve controlling said air-inlet; and a trip in saidtube adapted through engagement with the cartridge to open saidair-inlet valve; and means for automatically closing said airinlet valveafter the air-valve for the tube has been openedby said piston,substantially as described.

11. In a pneumatic-despatch-tube system, the combination of a tubeadapted to transmit a cartridge along same; a suction-pipe extendingalong said tube; a valve connecting said tube and pipe; a lever in saidtube adapted to engage the cartridge and close said valve; and 'meansfor automatically opening said valve after said cartridge has passed acertain distance beyond same, substantially as described.

12. In a pnemnatic-despatch-tube system, the combination of a tubeadapted to transmit a cartridge along same; a suction-pipe extendingalong said tube; a valve connecting said tube and pipe; means normallyurging said valve into a closed position; a detent adapted to hold thevalve open; and a trip extending into said tube and adapted throughengagement with said cartridge to release the valve from said detcnt,substantially as described.

13. In a pneumatic-despateh-tulle system. the combination ol a tubeadapted to transmit a cartridge along same; a gate extending across saidtube and dividing same into two sections; means for exhausting air fromeach of said sections; a suction-valve in the lirst sectioncommunicating with said means; a trip in said first section adaptedthrough engagement with a cartridge to close said suetion-valve beforethe arrival ol the cartridge, at the gate; and a trip in said seeondsection adapted through engagement with the cartridge to cause theopening of said suctionvalve after the cartridge. has passed the gate,substantially as described.

14:. In a pneumatic-despatch-tnbe system, the combination of a tubeadapted to transmit a cartridge along same; means lor exhausting the airfrom said tube; a stu:tion\'alve connecting said tube and said means; aspring normally urging the valve into its clo ed posit-ion; a detentadapted to hold said valve in its open position; and an arm extendinginto the tube and adapted through engagement; with the cartridge to movesaid detent and release the valve, substantially as described.

15. In a pnetnuatic-despateh-tulle system, the combination of a tubeadapted to transmit a cartridge along same; a gate extending across oneend of the tube and opening outward; a suction-pipe communicating wit hsaid tube near said gate, said suction-pipe being of considerably lessdiameter than said tube so that the air in advance of said cartridgewill tend to be compressd by the movement of the cartridge and check thespeed of same before its arrival at said gate, substantially asdescribed.

16. In a pneumatic-despatch-tulie system, the combination of a tubeadapted to transmit a cartridge along same; means for exhausting airfrom said tube; a despatch-box at one end of said tube adapted toreceive the cartridge and having its walls suitably formed to inclosesaid cartridge; a gate separating said dospatch-box from said tube; anair-passage extending through the walls ol said despatchbox and havingconsiderably less transverse area than said tube; an air-valvccommunicating with said tube at a point beyond said despatch-box; meansfor opening said gate; and means for openil'ig said air-valve alter thecartridge has passed said gate, substantially as described.

17. In a pneumatic-despateh-tube system, the combination of a tubeadapted to transmit a cartridge along same; means for exhausting airfrom said tube; a despateh-box at one end of said tube adapted toreceive the eartridge and having its walls suitably formed to inelose.said cartridge; a gate separating said despatehbox from'said tube; anair-passage extending through the walls of said despatchbox and havingconsiderably less transverse area than said tube; an air-valvecommunicating with said tube at a point beyond said gate; 'means foropening said gate; and mechanism for automatically opening saidair-valve in a certain predetermined interval after the opening of saidgate, sub'stantiallyas described.

18. In a pneumatic-despatch-tube system, the combination of a tubeadapted to transmit a cartridge along same; means for exhausting airfromsaid tube; aldespateh-box at one end of said tube adapted to receive thecartridge and having its walls suitably formed to inclose saidcartridge; a gate separating said despatehbox from said tube; anair-passage extending through the walls of said despatch-box and havingconsiderably less transverse area than said tube; anair-valvecommunicating with said tube at a point beyond said gate; means foropening said gate to cause the cartridge 'to enter the tube; means forautomatically closing said gate after the passage of the cartridge; andmechanism for automatically opening said air-valve in a certainpredetermined interval after the opening of said gate, substantially asdescribed.

19. In a pneumatic-despatch-tiibe system,

the combination of a tube adapted to transmit a cartridge along same;means for exhausting air from said tube; a despatch-box at one end boxfrom said tube; an air-passage extending through the Walls of saiddespateh-box and having considerably less transverse area than saidtube; an air-valve communicating with said tube at a point beyond saidgate; means for opening said gate to cause the cartridge to enter thetube; means for automatically closing said gate after the passage of thecartridge; -mechanism for automatically opening said air-valve in acertain predetermined interval after the opening of said gate; meansnormally urgingthe closing of said air-valve; and a timing device forcontrolling the closing of said air-valve, substantially as described.Signed at New York, N. Y., this 17th day of April, 1904:- y

. WILLIAM H. DINSPEL. -Witnesses:

' F. S. VAN VVART,

MAX GREENWALD. Signed at Chicago, Illinois.

JOSEPH J. STOETZEL. Witnesses: WILLIAM L. HALL, D. H. JACKMAN.

